(1) Field of the Invention
The present invention relates to a technique of a control valve configured to supply and distribute oil drained from an oil pump to a variable valve mechanism such as a valve timing control apparatus and each lubricating oil section of an internal combustion engine, a variable capacitance pump, and furthermore is a hydraulic pressure circuit of an internal combustion engine in which the same apparatus having the control valve and the variable capacitance pump is used.
(2) Description of Related Art
A hydraulic pressure which provides a driving source for a hydraulic pressure actuator of, for example, a hydraulic valve timing control apparatus is secured by a branch passage branched from a communication passage communicated with the oil pump and a main oil gallery. There is a high demand for improving an operation response characteristic of the valve timing control apparatus which is the hydraulic pressure actuator, especially the operation response characteristic immediately after the start of engine is high so that, in this case, a pump capacity of an oil pump is needed to be enlarged.
As the technique described in a Japanese Patent Application First Publication No. Showa 57-173513 published on Oct. 25, 1982 (this publication corresponds to a U.S. Pat. No. 4,452,188), a control valve which operates to open and close according to the hydraulic pressure is provided in an oil passage at a downstream side of a branch passage. When a drained pressure of an oil pump at a time of engine start is under a low pressure, oil is supplied with a higher priority to the valve timing control apparatus. When the drained pressure becomes high, the control valve is opened so that a drained flow quantity to a main oil gallery is controlled to become increased.